Anesthesia will be maintained with Propofol infusion at 5 - 10 mg/kg IBW/hour, lidocaine at 0,75 - 2,25 mg/kg IBW/h, Dexmedetomidine 0,5 - 1,4 ug/kg IBW/h and Ketamine 0,125 - 0,375 mg/kg IBW/h adapted according to Bispectral analysis (BIS) value ( keep below 60) and hemodynamic parameters (keep heart rate below 100 and SAP below 140mmHg).